Selectively overlaying a user interface atop a video signal

ABSTRACT

Overlaying visual interface information atop a video signal without obscuring desired features of the video signal. The video signal may contain one or more pre-selected features, such as text. Two or more display sections equally divide the video signal, and any pre-selected features in the video signal are identified as residing in particular display sections. Depending on the nature of the features, the selected visual interface information is placed atop the video signal in a display section not containing any pre-selected features so as not to cover or obscure the features or is placed over specified features that do not significantly contribute to the video signal, such as blank or static screen regions. A hierarchy of preferred display sections for placing the visual interface information may be created to optimize the placement thereof. The methods for overlaying visual interface information find particular application with interactive television systems.

CROSS-REFERENCE TO RELATED APPLICATIONS

Not applicable.

BACKGROUND OF THE INVENTION

1. The Field of the Invention

The present invention relates to video signals. More specifically, thepresent invention relates to methods, systems, and computer programproducts for selectively displaying a user interface atop a video signalin a televised or computerized system.

2. The Related Technology

A video display unit, such as a television or computer monitor, is anintegral component of many computerized systems. By displaying a videosignal on the screen of the television or computer monitor, a viewer isable to interact with the system. This interactive ability is central tointeractive television systems, where the display unit is continuouslyemployed not only to present information to the user, but also as ameans by which the user may input information to the interactive system.For example, interactive television systems may present additionalinteractive information on the screen of the television from time totime that is specifically synchronized to the program being shown. Thisadditional information may include information concerning the channel orprogram that is currently displayed, as well as one or more controloptions for viewer input. For instance, an interactive television systemmay allow the viewer to play along with a game show that is currentlydisplayed on the television screen. Thus, the ability of an interactivetelevision system to enhance the experience of the viewer by providingadditional interactive information on the screen, such as text andgraphics, is an important one.

The inclusion of additional interactive information on the televisionscreen by the interactive television system may be hampered, however, bytext, graphics, and other information that may be present as part of theoriginal video signal displayed on the television screen. For instance,the video signal of a typical television program that is displayed by aninteractive television system may include the name of a person orlocation shown on the screen that is usually displayed at the bottom ofthe screen, station and program identification watermarks that aretypically displayed in the corners of the screen, and sports scores,player statistics, or other miscellaneous information that may bedisplayed at various locations on the screen during an athletic event.This information often provides additional satisfaction for the viewer.Thus, if any of this original video signal information is obscured byadditional interactive information that is overlaid onto the screen bythe interactive television system, frustration of the viewer may result.

In addition to the text-based information explained above, otherfeatures or attributes may also be present in the original video signal.These features, such as the faces of characters on a television programor important objects of interest, are also typically desired for viewingby the viewer and should not be obscured by additional interactiveinformation overlaid by the interactive television system. Coveringthese and other desired objects of interest on the television screencreates confusion and frustration for the viewer.

Additionally, the placement of additional interactive information overareas of the video signal having certain attributes may also beproblematic. For instance, interactive information comprisinglight-colored text would be poorly viewed if overlaid atop alight-colored portion of the displayed video signal. This and otherproblems related to visual video signal attributes can further confuseand frustrate the viewer.

Several attempts have been made to deal with the problem describedabove. One attempt has involved shrinking the area of the screenoccupied by the video signal to a smaller relative size such that ablank area is provided about the perimeter of the video signal display.This enables the extra-perimeter area to be used for positioningadditional interactive information. However, this technique suffers fromseveral disadvantages. Text and other video signal information becomeless legible due to the smaller size of the display area. Also, thevideo image, given its smaller size, is less interesting to view.Further, the shrinking of the area occupied by the video signal canrequire substantial video processing, which may be impossible forcertain set-top boxes associated with interactive television systems.

Another attempt at adequately providing additional interactiveinformation has involved making the interactive information partlytransparent before overlaying it atop the already-existing video signal.Theoretically, the viewer will be able to view the additionalinteractive information displayed atop the video signal, while stillbeing able to see the underlying video signal. In practice, however, ithas been found that the opacity of the additional interactiveinformation must approach 70% for adequate comprehension. As may bepredicted, this correspondingly reduces the quality of the underlyingvideo signal. The result is additional interactive information thatserves only to distract the viewer and obscure desirable portions of thevideo signal.

It is noted that the problem of supplying additional information atop avideo signal having one or more features already present therein hasbeen partly addressed through human interaction. That is, a humanproducer at a television broadcast station, for instance, maydynamically determine where additional screen information should bedisplayed so as not to cover or obscure pre-existing text or otherfeatures on the screen. In short, the producer manually places theadditional information in an area of the screen that is not occupiedwith other desired visual information. While this technique may besuccessful for some systems, such as standard television broadcasting,it is limited because of its manual nature. Thus, this technique is notuseful for automatically displaying user interface information on anacceptable area of the television screen. Further, this solution doesnot have applicability to interactive television systems, which are moreautomated than standard television systems.

A need therefore exists to enable the placement of additionalinteractive information atop a video signal according to one or moreattributes of the video signal. More particularly, a need exists todisplay interactive information atop a video signal without obscuringspecified features, including text, faces, or other visual attributespresent in the video signal.

BRIEF SUMMARY OF THE INVENTION

The present invention relates to the display of user interfaceinformation atop a video signal according to the position of one or moreselected attributes that may be present in the video signal. This, inturn, enables the display of the user interface information on a videodisplay unit, such as a television monitor, in such a way as to optimizethe presentation of the information. In this way, text or other desiredvisual information already present in a video signal is not obscured bythe concurrent display of the user interface information. In oneembodiment, the user interface information is provided by a host systemsuch as an interactive television system, and is positioned atop thevideo signal based upon the recognition of one or more specifiedfeatures, which are comprised of attributes present in the video signal.The attribute(s) comprising the specified feature may be automaticallychosen by the host system, or may be defined by the user. Recognition ofthe presence and relative location of these pre-existing, specifiedfeatures in the video signal is performed prior to overlaying the userinterface information. Once the existence and location of the specifiedfeatures are identified in the video signal, an appropriate sizing andpositioning of the user interface information atop the video signal maythen be performed so as not to cover or obscure any of the specifiedfeatures. In this way, user interface information may be displayed onthe television screen or other video display unit without obscuringpre-existing features, such as faces, pre-existing text, and/or coloredareas of the screen.

The video signal is displayed via a video signal display unit, such as atelevision screen or monitor. A host system, such as an interactivetelevision system, video gaming unit, etc., provides the video signal tothe display unit. A feature detection module, which may be disposed inany one of several locations, includes hardware and/or programming codefor recognizing the presence and position of the attribute(s) of theselected features in the video signal. The information provided by thefeature detection module is then used by a user interface module fordetermining the best location for overlaying user interface informationatop the video signal. To do so, the user interface module firstvirtually subdivides the video signal into two or more sections, andassigns a hierarchy of preferred sections where the user interfaceinformation may be overlaid atop the video signal. The user interfacemodule then analyzes the information from the feature detection moduleto determine which sections already contain attributes comprising thepre-existing features. The hierarchy of preferred sections assigned bythe user interface module is then referred to, and the highest rankedsection that is not currently occupied by a selected feature isidentified. The user interface module overlays the user interfaceinformation atop that section. In overlaying the user interfaceinformation atop a preferred section, the user interface module mayutilize one of two or more defined sub-areas that comprise a specifiedportion of the section. In this way, the user interface information isplaced atop the section in a manner that obscures a relatively smallamount of the video signal. Examples of such sub-areas include ahorizontally extending rectangle, and a vertically extending rectangle.

The specified feature is comprised of one or more attributes of thevideo signal, including color, brightness, and high frequency (highdetail) regions in the signal. The attribute(s) comprising the specifiedfeature can be automatically chosen by the present system, or manuallyselected by the user.

In one alternative embodiment, the present invention can be utilized toplace user interface information atop the video signal such that itcovers specified feature attributes that are not critical to the viewingexperience, such as low frequency (blank) areas of the screen, oruniform color regions, such as an area of blue sky, for instance. Inthis way, the user interface information may be displayed withoutobscuring more important regions of the displayed video signal.

In another alternative embodiment, selected attributes of the userinterface information can be analyzed by the present system, thencompared to the attributes comprising the specified feature to enableoptimum placement of the user interface information. For example,analysis of the user interface information can reveal that it comprisestext having relatively high levels of brightness. The present system canthen determine optimum placement for the bright interface informationand place it on the screen so as to avoid an area where analysis by thesystem has revealed a similarly bright specified feature exists.

The present invention can be useful for enabling a computer system, suchas an interactive television system, to display additional userinterface information atop a video signal. Examples include displayingfurther information about the program currently being shown, anddisplaying user controls for enabling the viewer to interact with theprogram.

As described above, the location and shape of the user interfaceinformation to be displayed can be chosen according to which specifiedfeatures are currently present in the video signal. In anotherembodiment, however, the user interface information is placed not onlyaccording to which features are currently in the video signal, but alsowhich features are about to be displayed. Thus, the user interfacemodule anticipates the position of specified features and overlays itsuser interface information accordingly. Additionally, this enables thecontent of user interface information to be selected or adjustedaccording to what type of specified features is about to be displayed inthe video signal, by giving the user interface module or associateddevices time to search for and select the desired information.

These and other objects and features of the present invention willbecome more fully apparent from the following description and appendedclaims, or may be learned by the practice of the invention as set forthhereinafter.

BRIEF DESCRIPTION OF THE DRAWINGS

To further clarify the above and other advantages and features of thepresent invention, a more particular description of the invention willbe rendered by reference to specific embodiments thereof that areillustrated in the appended drawings. It is appreciated that thesedrawings depict only typical embodiments of the invention and aretherefore not to be considered limiting of its scope. The invention willbe described and explained with additional specificity and detailthrough the use of the accompanying drawings in which:

FIG. 1 illustrates various components with which the invention can beimplemented;

FIG. 2A is a view of a monitor or screen displaying a video signalcontaining a specified feature in one section thereof;

FIG. 2B is a view of the screen of FIG. 2A, also showing user interfaceinformation that has been overlaid atop another section of the videosignal;

FIG. 2C is yet another view of the screen of FIG. 2A, also showing userinterface information that has been overlaid atop a section of the videosignal, wherein the user interface information is enclosed within adiffering sub-area as compared to FIG. 2B;

FIG. 3 illustrates a flow chart showing various steps involved inexecution of the present invention according to one embodiment; and

FIG. 4 illustrates a system that provides a suitable operatingenvironment for embodiments of the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Reference will now be made to figures wherein like structures will beprovided with like reference designations. It is understood that thedrawings are diagrammatic and schematic representations of presentlypreferred embodiments of the invention, and are not limiting of thepresent invention nor are they necessarily drawn to scale.

FIGS. 1 through 4 depict various features of embodiments of the presentinvention, which is generally directed to selectively overlaying userinterface information atop a video signal containing specified features.

Reference is first made to FIG. 1, which depicts various componentscomprising a video signal display system, generally depicted at 100, andincorporating various elements of one embodiment of the presentinvention. As seen in FIG. 1, a source 102 provides a video signal 104over a transmission line 106. The video signal 104 is received by a hostsystem 108, which in the present embodiment comprises an interactivetelevision system. It is appreciated, however, that the host system 108can comprise other devices, such as a standard television, a gamingconsole, a computer, etc. Thus, though embodiments of the presentinvention disclosed herein will be described in connection with aninteractive television system, this is not meant to limit the presentinvention in any way.

The host system 108 transmits the received video signal 104 to a videosignal display unit 110. In the present embodiment, the video signaldisplay unit 110 comprises a television monitor having a display screen110A. Alternatively, the video signal display unit 110 can comprise acomputer monitor, or the like. The video signal 104 displayed by thevideo signal display unit 110 may comprise a television program, asports broadcast, or any other type of visual information.

The video signal 104 that is transmitted from the source 102 can includeregions characterized by one or more video signal attributes that aredisplayed on the video signal display unit 110. For instance, the videosignal display unit 110 as shown in FIG. 1 depicts a box of textresiding in the upper left corner of the screen 110A. This text may becharacterized by one or more attributes, such as the color of the text,or its brightness. The text shown in FIG. 1, having one or moreattributes as described here, is but one example of a specified feature112 which exists at a specified point in time as a component of thevideo signal 104. Indeed, the specified feature 112 may comprise one ormore of a variety of attributes that together can comprise recognizableobjects of the video signal 104, including text, human faces, graphics,animate or inanimate objects, etc. Also, more than one specified feature112 may be present in the video signal 104 at any given point in time.

As already suggested, the specified feature 112 of the present inventioncan be defined by one or more of a variety of attributes of the videosignal 104. For example, color attributes, such as a region of the bluesky, may comprise the specified feature 112. Brightness attributes ofthe video signal 104 may also be employed. An example of this includes aregion of the displayed video signal 104, such as an image of a light,that is brighter than other regions of the signal. Possible attributesalso include high image frequency regions of the video signal 104. Imagefrequency attributes of the video signal 104 include regions where highimage detail is present. Generally, this high detail can be detected bythe wealth of shapes and surfaces in the particular signal region.Frequency attributes associated with color and brightness can also beemployed. Further, a combination of these or other attributes notmentioned can be utilized to define the specified feature 112. Thespecified feature 112 can also be defined by the absence of a particularattribute. Thus, the enumeration of attributes above is not meant to bean exhaustive listing of all possible attributes that can be employed inconnection with the present invention.

The video signal display unit 110, in addition to the video signal 104,can also display on its screen 110A user interface information 114. Incontrast to the specified feature 112, which is typically an originalcomponent of the video signal 104, the user interface information 114 isplaced on the screen 110A atop the video signal by the host system 108.In other words, the user interface information 114 is overlaid upon thevideo signal 104 as displayed by the display unit 110. It is a featureof one embodiment of the present invention that the user interfaceinformation 114 is overlaid atop the video signal 104 in such a way asnot to overlap or obscure any specified feature 112, such as the box oftext shown in FIG. 1. Thus, the user interface information 114 isdisplayed atop the video signal 104 in an area where no other specifiedfeature 112 exists, so as not to obscure portions of the video signalthat the viewer likely wants to see. More details concerning this areset forth further below.

In one embodiment, the placement of the user interface information 114is determined by a user interface module 116 which, as shown in FIG. 1,comprises a portion of the host system 108. Alternatively, it isappreciated that the user interface module 116 may comprise a separatedevice from the host system 108. The specific acts and steps taken bythe interface module 116 to ensure the overlaying of user interfaceinformation 114 in such as way as not to obscure any specified features112 are discussed further below.

It is appreciated that the user interface information 114 may comprisetext, interactive controls, graphics, or other features that may bedisplayed to enhance the viewing experience of the viewer. For example,if the video signal 104 comprises a game show, the user interfaceinformation 114 may comprise a question related to the game show thatthe viewer may attempt to answer via the interactive television system.Thus, the question may be displayed in text-block format, such as thatshown on the screen 110A in FIG. 1.

A feature detection module 118 is also included as a component of thevideo signal display system 100, in accordance with one embodimentthereof. The feature detection module 118 is responsible for determiningwhether a specified feature 112 is present in the video signal 104, andif so, its position. As shown in FIG. 1, the feature detection module118 may be disposed at or near the source 102 of the video signal 104.However, it is appreciated that feature detection module 118 may resideat various locations along the path of the video signal 104, including alocation within or near the host system 108.

In greater detail, the feature detection module 118 in one embodimentcomprises hardware and/or programming code that enables it to recognizethe presence and location of attributes comprising one or more specifiedfeature in the video signal 104. In order to recognize the specifiedfeatures, the feature detection module 118 continuously analyzes thevideo signal 104. When a specified feature possessing the pre-determinedattributes is detected, the feature detection module 118 determines itslocation as it would be seen on the screen of the video display unit.This information is then be encoded into the video signal 104 for laterprocessing by the user interface module 116.

This encoding of the video signal 104 may include the insertion of oneor more triggers that identify the presence and location of thespecified feature 112. These triggers may then be detected and processedby the user interface module 116 to enable adequate placement of theuser interface information 114, as explained further below. It isappreciated, however, that there are a variety of ways by which thefeature detection module 118 may signal the presence and location ofspecified features 112 in the video signal 104. Thus, the above encodingmethod is not meant to limit the present invention in any way.

As described above, the specified feature 112 detected by the featuredetection module 118 may comprise attributes associated with text, suchas a sporting event box score or the identification of a person shown inthe video signal 104. However, the feature detection module 118 may alsobe configured to recognize and identify other specified features 112having attributes indicative of an object, such as a human face, or aregion of the video signal 104 where a certain color is predominant. Ifdesired, more than one type of specified feature may be designated to besimultaneously searched for in the video signal 104 by the featuredetection module 118. For instance, the feature detection module may beconfigured to search for and identify blocks of text as well as areas ofthe video signal 104 where high brightness is present. The designationof which video signal attributes will be searched for as specifiedfeatures, the number of specified feature types to search for, and othersimilar feature detection details may be pre-programmed into the featuredetection module 118, or they may be user-definable, according to theparticular configuration of the video signal display system 100. Thefeature detection capabilities of the feature detection module 118 areknown and described in the art, and thus are not discussed in furtherdetail here.

As described above, the location of the feature detection module 118 maybe chosen as necessary to suit the particular application involved. Asillustrated in FIG. 1, the feature detection module 118 may beincorporated as a component at or near the source 102 of the videosignal 104, comprising part of a video processor, for example, that isconfigured to analyze the video signal prior to uplink and transmission.In this configuration, the video signal 104 is analyzed by the featuredetection module 118 before it is transmitted via the transmission lines106 to one or more host systems 108. Thus, the identification andanalysis of specified features 112 is performed by the feature detectionmodule 118 to the video signal 104 as a whole. This means that each hostsystem 108 connected to the transmission line 106 receives a videosignal that has the specified features 112 identically detected withinit.

In contrast, it is appreciated that in some embodiments the featuredetection module 118 can alternatively be disposed at or near the hostsystem 108 so as to be accessible and programmable by the user of thehost system. For instance, in one example, the feature detection module118 comprises a portion of an interactive television set-top boxcomprising the host system 108. This configuration enables the viewer toprogram the feature detection module 118 concerning which specifiedfeatures 112 the viewer desires the module to detect. As an example ofthis, the viewer may wish that the user interface information 114 thatis to be displayed by the user interface module 116 does not obscure thefaces of characters that appear in the video signal 104. Thus, theviewer can program the feature detection module 118 to identify thepresence and location of attributes typically indicative of facesappearing in the video signal 104. As already mentioned, thisinformation provided by the feature detection module 118 then enablesthe user interface module 116 to appropriately display user interfaceinformation 114 atop the video signal 104 without obscuring or coveringthe faces that may be present.

In greater detail, the user interface module 116 in one embodimentcomprises hardware and/or programming code for determining the optimumplacement of the user interface information 114 atop the video signal104. This may be accomplished via several functions performed by theuser interface module 116, including the virtual parsing of the videosignal 104 into two or more display sections. These displays sectionsmay be thought of as defining distinct areas on the screen 110A of thedisplay unit 110 where user interface information 114 may be placed.Additionally, the user interface module 116 also may assign a hierarchyof preferred display sections where a particular type of user interfaceinformation 114 would preferably be placed. For example, user interfaceinformation that consists of interactive game show questions may best beplaced in the upper right-hand corner of the interactive televisionscreen. Thus, the user interface module 116 may assign a hierarchy ofpreferred display sections where the game show question may be placed,wherein the display section corresponding to the upper right-handportion of the screen is the most preferred display section to be used.This and other functions of the user interface module 116 are explainedin further detail below in connection with FIGS. 2A–2C.

It should be noted here that the above description in connection withFIG. 1 is but one embodiment of the present invention, which enablesuser interface information to be overlaid atop a video signal. It is, ofcourse, appreciated that the functionality of the present inventiondescribed above can also be achieved by other components and devices.

Attention is now directed to FIGS. 2A–2C, which depict various views ofthe screen 110A of the video signal display unit 110, including variousscreen elements. In FIG. 2A, the specified feature 112 comprises text,as previously shown in FIG. 1. As can be seen from the figure, thescreen 110A has superimposed thereon a series of four quadrants numberedI–IV. These quadrants, referred to here as display sections 120,represent the virtual division of the displayed video signal 104 by theuser interface module 116. The division of the screen 110A into the fourdisplay sections 120 is not a physical division such that the dasheddividing lines are seen by a viewer; rather, it is a virtual divisionfor facilitating the placement by the user interface module 116 of userinterface information 114 atop the video signal 104 without obscuringany specified features 112, such as that shown in FIG. 2A. Though thescreen 110A is shown in FIG. 2A as being divided into four displaysections 120, it will be appreciated that the screen can be virtuallydivided into more or fewer sections than this, if desired, to suit aparticular application. For instance, two display sections 120 canalternatively be used to bisect the screen 110A.

In accordance with one embodiment of the present invention, the featuredetection module 118 determines during transmission of the video signal104 that a specified feature 112 not only is present in the videosignal, but also that it resides within the display section 120represented by quadrant II, as defined by the user interface module 116.This information is then used by the user interface module 116 in orderto display any desired user interface information 114 atop the videosignal 104, according to the operation of the host system 108.

FIG. 2B shows an example of one embodiment of the present inventionwhereby user interface information 114 is displayed along with thespecified feature 112, on the screen 110A of the video display unit 110.The placement of the user interface information 114 in quadrant IV ofthe display sections 120 illustrates the operation of the presentinvention, wherein the user interface information is placed in an areaof the screen 110A where obscuring of any specified features 112 willnot occur. In this way, only areas of the video signal 104 where nospecified features 112 are found will be occupied with user interfaceinformation 114. Further, the method by which this is accomplishedoccurs automatically, thereby eliminating the need for humanintervention in displaying the user interface information 114. In thisway, both user interface information 114 and any specified features 112are able to co-exist as displayed by the video signal display unit 110without obstruction or obscuring of either feature.

It should be noted that the user interface information 114 might also bedesirably placed within either quadrants I or III of the displaysections 120, given the fact that no specified features 112 exist inthose quadrants in FIG. 2B. However, in accordance with one embodimentof the present invention, quadrant IV was chosen by the user interfacemodule 116 as the preferred location for displaying user interfaceinformation 114. As explained earlier, this quadrant may be chosenaccording to a hierarchy defined by the user interface module 116 thatdetermines which quadrant is most preferred to display the userinterface information 114, which quadrant is the next-most preferred fordisplaying the information, which quadrant is the third-most preferredquadrant, etc. Thus, if the most preferred quadrant according to themodule-defined hierarchy is occupied by one or more specified features112, selection by the user interface module 116 of the next-mostpreferred quadrant having no specified features therein will occur.

It should be appreciated that more than one specified feature 112 mayexist on the screen 110A of the video signal display unit 110 such thatmore than one of the display sections 120 are occupied with suchfeatures. In this case, the hierarchy of preferred display sections 120in which the user interface information 114 should most desirably bedisplayed is scanned until a display section is found in which nospecified features 112 are encountered. Thus, the user interfaceinformation 114 is placed in the highest ranked display section 120 inwhich none of the specified features 112 is found.

Reference is now made to FIG. 2C, which shows the specified feature 112and user interface information 114 displayed on the screen 110A, similarto FIG. 2B. In contrast to FIG. 2B, however, FIG. 2C shows the userinterface information 114 occupying a differently shaped informationsub-area 122B within quadrant IV of the display sections 120. The userinterface module 116 may define one or more information sub-areas 122 inwhich the user interface information 114 may be displayed. For instance,FIG. 2B shows the user interface information 114 contained within aninformation sub-area 122A that comprises a horizontally extendingrectangle within quadrant IV. In contrast to this, FIG. 2C shows thesame user interface information 114 displayed in a vertically extendingrectangle. Thus, one or more information sub-areas 122 may be defined bythe user interface module 116 for containing the text and/or otherfeature comprising the user interface information 114. Additionally,these shapes may be user-defined within the host system 108 such that aviewer may specify the shapes of the information sub-area 122 in whichthe user interface information 114 will be contained. For instance, aviewer may designate that user interface information 114 is displayed ina vertical rectangle information sub-area 122B as that shown in FIG. 2C,thereby freeing up more space towards the middle of the screen 110Awhere faces and other interesting features of the video signal 104 aretraditionally displayed. Alternatively, the shapes of the informationsub-area 122 may be automatically chosen and/or encoded into the userinterface module 116 or host system 108.

In addition to the shapes of the information sub-areas 122, which in oneembodiment may be user-defined as discussed above, other aspects of thepresent invention may also be user-definable. For example, the number ofdisplay sections 120 that are used by the feature detection module 118and the user interface module 116 may be user-defined. Similarly, thepreferred hierarchy of display sections 120 can be defined by the user,as well as how often user interface information 114 is displayed on thescreen 110A. Also, the user may define which specified features 112should be avoided by the user interface module 116 when deciding whereto position the user interface information 114. For example, the usercan define that faces are not to be covered by user interfaceinformation 114, or that text appearing in the upper left-hand displaysection of the screen 110A, where sporting event box scorestraditionally appear, should not be covered. Thus, various parameters ofthe present invention may be either automatically defined by the userinterface module 116, or by the user of the host system 108, dependingon the particular application.

In another embodiment of the present invention, the video signal displaysystem 100 can be programmed to overlay the user interface information114 atop the video signal 104 in order to cover the specified feature112. This may occur where the specified feature 112 comprises attributesof the video signal that would not significantly detract from theviewing experience if obscured by the user interface information 114.Examples of such attributes of the video signal 104 include low colorfrequency regions, such as black regions at the top and bottom of thescreen 110A that are present in “letterbox” display formats, blue skyareas, or the green fairway regions that may be present in a golfingbroadcast. For instance, blue sky may be either automatically oruser-selected as the attribute comprising the specified feature 112 overwhich the user interface information 114 may be placed. In this case,the feature detection module 118 searches for any portions of the videosignal 104 containing regions of blue sky. When such regions having thiscolor frequency attribute are found and located, the user interfaceinformation 114 can then be overlaid atop the display section 120containing the blue sky region by the user interface module 116. If noblue sky regions are present in the video signal 104, the user interfacemodule 116 can select the next preferred location in which to place theuser interface information 114. Thus, in general, the location where thevisual interface information is to be displayed is selected with respectto the position of the specified feature and is selected either toobscure or to not obscure the specified feature, depending on the natureof the selected feature.

It is also appreciated that the user interface module 116 can choose thelocation for display of the user interface information 114 according tothe detection of regions of the video signal 104 that are static over aspecified period of time, i.e., regions where no dynamic change of thevideo display occurs over time. In this case, the user interface module116 can overlay the user interface information 114 atop these staticregions. These static regions can be detected by the feature detectionmodule 118, or other suitable video signal processor. In oneimplementation, the static regions are identified by analyzing acompressed digital video stream to identify skipped macroblocks. Skippedmacroblocks generally represent portions of the video image that arestatic over time. Macroblocks representing the user interface data arethen substituted for the skipped macroblocks or the user interface isotherwise combined with or overlaid on the static portion of the image.

In yet another embodiment of the present invention, the user interfacemodule 116 can choose the location for display of the user interfaceinformation 114 based on an analysis and comparison by the featuredetection module 118 and/or the user interface module 116 of selectedattributes of both the specified feature 112 and the user interfaceinformation itself. In one implementation of this embodiment, selectedattributes of the specified feature 112 are detected by the featuredetection module 118 and received by the user interface module 116. Theuser interface module 116 then compares these attributes to the selectedattributes of the user interface information 114 and determines theoptimum display section 120 in which to display the information. Forexample, the selected attribute may comprise color. Thus, when aspecified feature 112 having the selected color attribute is detected bythe feature detection module 118, this information is relayed to andreceived by the user interface module 116. The user interface module116, either before or after receipt of the information from the featuredetection module 118, analyzes the color attributes of the userinterface information 114 to be displayed, then compares its attributesto those of the specified feature 112. The user interface module 116then determines from this comparison of the color attributes where toplace the user interface information 114 so as to optimize itspresentation atop the video signal 104. For instance, this placement mayprevent blending of the colors of the specified feature 112 and thedisplayed user interface information 114 so that the viewer may easilyread the presented information on the screen 110A. The selectedattributes to be compared between the specified feature 112 and the userinterface information 114 can be automatically chosen by components ofthe display system 100, or may be selected by the user.

Embodiments of the present invention may be described in terms ofmethods comprising functional steps and/or non-functional acts. Thefollowing is a description of acts and steps that may be performed inpracticing the present invention. Usually, functional steps describe theinvention in terms of results that are accomplished, whereasnon-functional acts describe more specific actions for achieving aparticular result. Although the functional steps and non-functional actsmay be described or claimed in a particular order, the present inventionis not necessarily limited to any particular ordering or combination ofthe acts and/or steps.

FIG. 3 illustrates a flow diagram showing acts and steps for a method ofoverlaying user interface information atop a video signal according toone embodiment of the present invention. An act 200 includes inputting avideo signal 104 that may contain one or more specified features 112, asexplained above. A step 210 for determining the position of a specifiedfeature 112 in the video signal 104 may include an act 212 of parsingthe video signal into two or more display sections 120. For example, thevideo signal 104 as shown in FIGS. 2A–2C has been parsed into fourdisplay sections 120, shown as four quadrants.

The step 210 for determining the position of a specified feature 112 inthe video signal 104 may further include an act 214 of inquiring ofwhether the specified feature 112 is detected in the video signal 104.If the inquiry of act 214 is answered in the negative, control isreturned to act 200. However, if act 214 is answered in the affirmative,control is transferred to act 216, which also comprises a part of thestep 210. Specifically, act 216 includes determining in which displaysection(s) 120 of video signal 104 a specified feature 112 exists. Forexample, in FIG. 2A the specified feature 112 is found in quadrant II ofthe display section 120.

The information acquired from step 210 for determining the position of aspecified feature 112 in video signal 104 may, in one embodiment, beencoded as a trigger directly into the video signal. In this way, theinformation acquired by step 210 may be used in later steps.

The method illustrated in FIG. 3 further comprises a step 220 fordisplaying user interface information 114 without obscuring thespecified feature 112. Step 220 may include an act 222 of placing theuser interface information 114 in a display section 120 of the videosignal 104 where no specified feature 112 is present. In one embodiment,act 222 may be accomplished by detecting the trigger previously encodedin the video signal 104 and using the information provided by thattrigger to determine which display sections 120 are free from thespecified feature 112, thereby enabling placement in those sections ofthe user interface information 114. For example, a trigger encoded by afeature detection module 118 into the video signal 104 may be detectedby the user interface module 116 (see FIG. 1). The trigger preferablycontains information concerning which specified features 112 are presentin the video stream 104, and in which display section the feature willbe displayed. This trigger information then enables the user interfacemodule 116 to place user interface information 114 in one or more of thenon-occupied display sections 120.

In one embodiment, act 222 may also involve creating a hierarchy ofpreferred display sections 120 where user interface information 114 isdesirably displayed atop the video signal 104, subject to the presenceof specified features 112 therein.

Once the user interface information 114 has been appropriately placedatop the video signal 104 such that no specified feature 112 is obscuredthereby, the information may remain displayed for a pre-determinedamount of time, or until the user takes action to remove it from thescreen. During the time that the user interface information 114 isdisplayed atop the video signal 104, it may be possible that a specifiedfeature 112 may appear underneath the user interface information as partof the continually changing video signal 104. If this occurs,embodiments of the present invention provide options whereby the userinterface information 114 either remains in its original location, isautomatically moved to the next preferred display section 120 accordingto the hierarchy of desired sections created by the user interfacemodule 116, or is automatically removed.

It is appreciated that in some instances no specified feature 112 may bedetected by the feature detection module 118. If this occurs, the userinterface module can place the user interface information in a specifieddisplay section 120 according to a preferred hierarchy of such sectionsas determined by the user interface module 116.

In one embodiment, the specified feature 112 comprises attributesrelated to a block of text as shown in FIGS. 2A–2C. In otherembodiments, and as already discussed, the specified features cancomprise other attributes as described above, such as brightness orcolor regions of the video signal 104. In the latter case, the presentinvention provides for the identification and localization of such colorregions so as to enable the placement of user interface information 114such that it avoids the colored area. This may be desirable, forexample, to ensure contrast between the color of the text of the userinterface information 114 and the background color region in the videosignal 104. This feature of the present invention may also be desirablyapplied to subtitling applications, where light colors could be detectedin the underlying video signal on a television screen, which wouldotherwise obscure the traditionally white text of subtitles, therebypreventing an easy reading thereof by the user. In this case, thesubtitles may be moved by the present invention to another displaysection 120 or, alternatively, the user interface module 116 may changethe color of the text comprising the subtitles so that they are easilyseen atop the light colored area present in the video signal 104. Theseand other scenarios illustrate but a few of benefits derived fromembodiments of the present invention.

As suggested above, the user interface information 114 may comprisetext-based subtitles or captions. In one embodiment, the user interfaceinformation 114, comprising subtitles, captions, or other information,may be input into the user interface module 116 via a data stream thatis separate from the video signal 104, or from a data stream transmittedas a discrete component of the video signal. In either case, the userinterface module 116 or other suitable video processing component cancombine the separate data, comprising the user interface information114, with the video signal 104 and display them in accordance with theprinciples described herein.

This embodiment can find particular application in standard,non-interactive television systems, and can be applied at any of severalpoints in the video signal distribution chain, such as at the televisionor set-top box, at the source of creation or transmission of the videosignal, or at a regional receiver that services multiple televisionterminals. Examples of the source of creation or transmission of a videosignal include a television broadcaster, a satellite transmitter, acable head end, and the like. Examples of regional receivers includevideo signal receivers operated by businesses, schools, airports, or inother settings where a single receiver is used for multiple televisionterminals. In those situations where the user interface information 114is combined at some point upstream of the television or set-top box, theuser interface module 116 is located at the upstream point in the videosignal distribution chain.

It is appreciated that at times the specified feature 112 may occupyportions of more than one display section 120. If this occurs,embodiments of the present invention provide for positioning of the userinterface information 114 in a display section 120 where no portion ofthe specified feature 112 is present. Should the specified feature 112occupy portions of all display sections 120 of the video signal 104, anautomatic or user-defined decision can be made beforehand that wouldprovide either that the user interface information 114 is not displayedat all, or that the best possible display section obscuring the leastamount of the specified feature 112 is chosen for overlaying the userinterface information.

Embodiments of the present invention can be configured to detect andaccount for moving as well as stationary specified features 112. Thedetected movement is then taken into account when determining in whichdisplay section 120 to display the user interface information 114. Theability of the present invention to account for moving specifiedfeatures 112 can also find applicability where the specified feature isthe face of a character or actor displayed in the video signal 104 ontelevision and who may continuously move from display section todisplay. This movement can be accounted for by the user interface module116 in determining where to place the user interface information 114 soas to obscure as little as possible of the face of the character.

In yet another embodiment, the present invention incorporates a videosignal buffer or similar device in order to anticipate upcoming changesin the presence and/or location of specified features 112 in the videosignal 104. Such changes to the specified feature 112 include theupcoming appearance of text, or the movement of text already present inthe video signal 104 from one display section 120 to another. The use ofa signal buffer enables the user interface module 116 to determine whereand/or whether to position the user interface information 114 accordingnot only to what is presently displayed in the video signal 104, butalso according to what will be displayed at a predetermined future pointin time.

The use of a signal buffer or similar device also enables embodiments ofthe present invention to select items to be displayed as user interfaceinformation 114 according to the type of specified feature 112 that isabout to be displayed in the video signal 104. In other words, thesignal buffer temporarily suspends successive portions of the videosignal 104, which in turn gives the user interface module 116 enoughtime to look for and select information that is complementary to theupcoming specified feature 112 about to be released from the signalbuffer and displayed in the video signal. This correlation between thecontent of the upcoming specified feature 112 and the user interfaceinformation 114 requires some analysis of the nature and content of thespecified feature about to be displayed. An overlay buffer may also berequired to further correlate the display of the user interfaceinformation 114 with the upcoming specified feature 112, as may beappreciated by one skilled in the art.

FIG. 4 illustrates an example system that provide suitable operatingenvironment for the present invention. Embodiments within the scope ofthe present invention may comprise one or more special purpose and/orone or more general purpose computers including various computerhardware, as discussed in greater detail below. However, it should beemphasized that the present invention is not necessarily limited to anyparticular computerized system. The following examples systems,therefore, should not be interpreted as imposing any particularenvironmental requirements on the present invention.

Embodiments within the scope of the present invention also includecomputer-readable media for carrying or having computer-executableinstructions or data structures stored thereon. Such computer-readablemedia can be any available media that can be accessed by a generalpurpose or special purpose computer. By way of example, and notlimitation, such computer-readable media may comprise physical storagemedia such as RAM, ROM, EEPROM, CD-ROM or other optical disc storage,magnetic disk storage or other magnetic storage devices, or any othermedium which can be used to carry or store desired program code means inthe form of computer-executable instructions or data structures andwhich can be accessed by a general purpose or special purpose computer.When information is transferred or provided over a network or anothercommunications connection (either hardwired, wireless, or a combinationof hardwired or wireless) to a computer, the computer properly views theconnection as a computer-readable medium. Thus, any such connection isproperly termed a computer-readable medium. Combinations of the aboveshould also be included within the scope of computer-readable media.Computer-executable instructions comprise, for example, instructions anddata which cause a general purpose computer, special purpose computer,or special purpose processing device to perform a certain function orgroup of functions.

FIG. 4 and the following discussion are intended to provide a brief,general description of a suitable computing environment in which theinvention may be implemented. Although not required, the invention maybe described in the general context of computer-executable instructions,such as program modules, being executed by computers in networkenvironments. Generally, program modules include routines, programs,objects, components, data structures, etc. that perform particular tasksor implement particular abstract data types. Computer-executableinstructions, associated data structures, and program modules representexamples of the program code means for executing steps of the methodsdisclosed herein. The particular sequence of such executableinstructions or associated data structures represents examples ofcorresponding acts for implementing the functions described in suchsteps.

Those skilled in the art will appreciate that the invention may bepracticed in network computing environments with many types of computersystem configurations, including personal computers, hand-held devices,television set-top boxes, multi-processor systems, microprocessor-basedor programmable consumer electronics, network PCs, minicomputers,mainframe computers, and the like. The invention may also be practicedin distributed computing environments where tasks are performed by localand remote processing devices that are linked (either by hardwiredlinks, wireless links, or by a combination of hardwired or wirelesslinks) through a communications network. In a distributed computingenvironment, program modules may be located in both local and remotememory storage devices.

With reference then to FIG. 4, an exemplary system for implementing theinvention includes a general purpose computing device in the form of aconventional computer 420, including a processing unit 421, a systemmemory 422, and a system bus 423 that couples various system componentsincluding the system memory 422 to the processing unit 421. The systembus 423 may be any of several types of bus structures including a memorybus or memory controller, a peripheral bus, and a local bus using any ofa variety of bus architectures. The system memory includes read onlymemory (ROM) 424 and random access memory (RAM) 425. A basicinput/output system (BIOS) 426, containing the basic routines that helptransfer information between elements within the computer 420, such asduring start-up, may be stored in ROM 424.

The computer 420 may also include a magnetic hard disk drive 427 forreading from and writing to a magnetic hard disk 439, a magnetic diskdrive 428 for reading from or writing to a removable magnetic disk 429,and an optical disc drive 430 for reading from or writing to removableoptical disc 431 such as a CD-ROM or other optical media. The magnetichard disk drive 427, magnetic disk drive 428, and optical disc drive 430are connected to the system bus 423 by a hard disk drive interface 432,a magnetic disk drive-interface 433, and an optical drive interface 434,respectively. The drives and their associated computer-readable mediaprovide nonvolatile storage of computer-executable instructions, datastructures, program modules and other data for the computer 420.Although the exemplary environment described herein employs a magnetichard disk 439, a removable magnetic disk 429 and a removable opticaldisc 431, other types of computer readable media for storing data can beused, including magnetic cassettes, flash memory cards, digitalversatile discs, Bernoulli cartridges, RAMs, ROMs, and the like.

Program code means comprising one or more program modules may be storedon the hard disk 439, magnetic disk 429, optical disc 431, ROM 424 orRAM 425, including an operating system 435, one or more applicationprograms 436, other program modules 437, and program data 438. Thesystem also includes a television 447 or another display device on whichthe video signals, with the overlaid user interfaces of the invention,are displayed.

The computer 420 may operate in a networked environment using logicalconnections to one or more remote computers, such as remote computers449 a and 449 b. Remote computers 449 a and 449 b may each be anotherpersonal computer, a server, a router, a network PC, a peer device orother common network node, and typically include many or all of theelements described above relative to the computer 420, although onlymemory storage devices 450 a and 450 b and their associated applicationprograms 436 a and 436 b have been illustrated in FIG. 4. The logicalconnections depicted in FIG. 4 include a local area network (LAN) 451and a wide area network (WAN) 452 that are presented here by way ofexample and not limitation. Such networking environments are commonplacein office-wide or enterprise-wide computer networks, intranets and theInternet.

The present invention may be embodied in other specific forms withoutdeparting from its spirit or essential characteristics. The describedembodiments are to be considered in all respects only as illustrative,not restrictive. The scope of the invention is, therefore, indicated bythe appended claims rather than by the foregoing description. Allchanges that come within the meaning and range of equivalency of theclaims are to be embraced within their scope.

1. In a computerized system having a display unit for displaying a videosignal, a method of selectively overlaying visual interface informationatop the video signal, the video signal capable of including at leastone specified feature, the method comprising acts of: parsing the videosignal into at least two display sections; searching the video signalfor the at least one specified feature; if the at least one specifiedfeature is not detected in the video signal, selectively placing thevisual interface information in at least one of the display sections; ifthe at least one specified feature is detected in the video signal,examining the video signal to determine in which display section the atleast one specified feature is located; and selectively placing thevisual interface information atop the displayed video signal in adisplay section where the at least one specified feature is not present.2. A method as defined in claim 1, further comprising an act of:creating a hierarchy of preferred display sections for placing thevisual interface information atop the displayed video signal, whereinthe visual interface information is placed in the most preferred displaysection where the at least one specified feature is not present.
 3. Amethod as defined in claim 1, wherein the act of parsing the videosignal further comprises an act of: parsing the video signal into atleast four display sections that equally divide the video signal.
 4. Amethod as defined in claim 1, wherein the act of placing the visualinterface information atop the displayed video signal further comprisesan act of: defining at least two shapes, one shape of which is used todefine the boundaries in which the visual interface information isplaced in a display section.
 5. A method as defined in claim 1, furthercomprising an act of: encoding the video signal with informationconcerning the presence and the location of the at least one specifiedfeature that is detected in the video signal.
 6. A method as defined inclaim 1, further comprising an act of: defining the at least onespecified feature as a result of input into the computerized system. 7.A method as defined in claim 1, wherein the at least one specifiedfeature comprises at least one attribute of the video signal selectedfrom the group consisting of text, color, brightness, frequency, and anycombination of these attributes.
 8. A method as defined in claim 1,wherein the at least one specified feature comprises a region of thevideo signal having a high visual frequency.
 9. A method as defined inclaim 1, wherein the visual interface information comprises text, andwherein the at least one specified feature comprises a region of colorpresent in the video signal.
 10. A method as defined in claim 1, whereinthe visual interface information comprises text-based subtitles.
 11. Amethod as defined in claim 1, wherein the computerized system is capableof receiving broadcast video data and is capable of interacting with oneor more servers over a computer network.
 12. For a computerized systemhaving a display unit for displaying a video signal, a computer programproduct carrying executable instructions that implement a method ofselectively overlaying visual interface information atop the videosignal, the video signal capable of including at least one specifiedfeature, the method comprising acts of: parsing the video signal into atleast two display sections; searching the video signal for the at leastone specified feature; if the at least one specified feature is notdetected in the video signal, selectively placing the visual interfaceinformation in at least one of the display sections; if the at least onespecified feature is detected in the video signal, examining the videosignal to determine in which display section the at least one specifiedfeature is located; and selectively placing the visual interfaceinformation atop the displayed video signal in a display section wherethe at least one specified feature is not present.
 13. A computerprogram product as defined in claim 12, further comprising an act of:creating a hierarchy of preferred display sections for placing thevisual interface information atop the displayed video signal, whereinthe visual interface information is placed in the most preferred displaysection where the at least one specified feature is not present.
 14. Acomputer program product as defined in claim 12, wherein the act ofparsing the video signal further comprises an act of: parsing the videosignal into at least four display sections that equally divide the videosignal.
 15. A computer program product as defined in claim 12, whereinthe act of placing the visual interface information atop the displayedvideo signal further comprises an act of: defining at least two shapes,one shape of which is used to define the boundaries in which the visualinterface information is placed in a display section.
 16. A computerprogram product as defined in claim 12, further comprising an act of:encoding the video signal with information concerning the presence andthe location of the at least one specified feature that is detected inthe video signal.
 17. A computer program product as defined in claim 12,wherein the method further comprises an act of: defining the at leastone specified feature as a result of user input into the computerizedsystem.
 18. In a computerized system having a display unit fordisplaying a video signal, a method of selectively overlaying visualinterface information atop the video signal, the video signal includingat least one specified feature, the method comprising acts of: providinga signal buffer that receives the video signal and outputs a bufferedvideo signal; parsing the buffered video signal into at least twodisplay sections; searching a portion of the buffered video signal forthe at least one specified feature; if the at least one specifiedfeature is detected in the portion of the buffered video signal,examining the portion of the buffered video signal to determine in whichdisplay section the at least one specified feature will be located whenthe portion of the buffered video signal is displayed; and selectivelyplacing the visual interface information atop the displayed portion ofthe buffered video signal in a display section where the at least onespecified feature is not present.
 19. A method as defined in claim 18,further comprising acts of: searching a successive portion of thebuffered video signal to determine if the at least one specified featureis still present; if the at least one specified feature is stillpresent, examining the successive portion of the buffered video signalto determine in which display section the at least one specified featurewill be located when the successive portion of the buffered video signalis displayed; and if needed, selectively moving the visual interfaceinformation that is displayed atop the displayed successive portion ofthe buffered video signal to a display section where the at least onespecified feature is not present.
 20. A method as defined in claim 18,further comprising an act of: choosing the content of the visualinterface information to be selectively displayed according to thecontent of the at least one specified feature.